CAPE CANAVERAL, Fla. - John Glenn joined the proud, surviving veterans of NASA’s Project Mercury on Saturday in celebrating the 50th anniversary of his historic orbital flight.

The first American to orbit the Earth, later a U.S. senator from Ohio, thanked the approximately 125 retired Mercury workers, now in their 70s and 80s, who gathered with their spouses at Kennedy Space Center to swap stories, pose for pictures and take a bow.

“There are a lot more bald heads and gray heads in that group than others, but those are the people who did lay the foundation,” the 90-year-old Glenn said at an evening ceremony attended by NASA officials, politicians, astronauts and hundreds of others.

“We may be up on the point of that thing and get a lot of the attention, and we had ticker-tape parades and all that sort of thing. But the people who made it work … you’re the ones who deserve the accolade. So give yourselves a great big ovation,” Glenn said, leading the crowd in applause.

Glenn and fellow astronaut Scott Carpenter, 86, spent nearly an hour before the ceremony being photographed with the retirees, posing for individual pictures in front of a black curtain with a model of a Mercury-Atlas rocket. Glenn and Carpenter are the lone survivors of NASA’s original Mercury 7 astronauts.

Earlier in the day, the Mercury brigade traveled by bus to Launch Complex 14. That’s the pad from which Glenn rocketed away on Feb. 20, 1962.

Some retirees were in wheelchairs, while others used walkers or canes. Most walked, some more surely than others. But they all beamed with pride as they took pictures of the abandoned pad and of each other, and went into the blockhouse to see the old Mercury photos on display and to reminisce.

As retired engineer Norm Beckel Jr. rode to the pad Saturday, he recalled being seated in the blockhouse right beside Carpenter as the astronaut called out to Glenn right before liftoff, “Godspeed John Glenn.”

But there’s more to the story.

“Before he said that, he said, `Remember, John, this was built by the low bidder,’” Beckel, 81, told The Associated Press.

The Mercury-Atlas rocket shook the domed bunker-like structure, although no one inside could hear the roar because of the thick walls.

“Nothing was said by anybody until they said, `He’s in orbit,’ and then the place erupted,” Beckel recalled.

Beckel and Jerry Roberts, 78, a retired engineer who also was in the blockhouse that historic morning, said almost all the workers back then were in their 20s and fresh out of college. The managers were in their 30s. “I don’t know if I’d trust a 20-year-old today,” Beckel said.

“They don’t know it, but we would have worked for nothing,” said Roberts, who spends the winter in Florida.

Bob Schepp, 77, who like Beckel traveled from St. Louis, Mo., for the reunion, was reminded by the old launch equipment of how rudimentary everything was back then.

“I wonder how we ever managed to launch anything in space with that kind of stuff,” Schepp said. “Everything is so digital now. But we were pioneers, and we made it all work.”

The Mercury team included women, about 20 of whom gathered for the anniversary festivities. One pulled aside an AP reporter to make sure she knew women were part of the team.

“Most of the women here are wives,” said Lucy Simon Rakov, 74. But not her.

“We weren’t secretaries. We were mathematicians,” said Rakov, a pioneering computer programmer who traveled from Boston for the reunion.

Patricia Palombo, 74, also a computer programmer, said working on Project Mercury proved to be the most significant thing she’s done in her career.

Glenn’s flight was the turning point that put America on a winning path that ultimately led to the moon.

“It’s been downhill from here,” Palombo said with a laugh. She lives near Washington, D.C.

Roberts praised the wives who endured the hardships back then. He recalled how he and his colleagues worked 16- and 18-hour days, seven days a week, especially after the Soviet Union grabbed the prize of first spaceman with Yuri Gagarin in 1961. Gagarin reached orbit on his mission; another Soviet cosmonaut also rocketed into orbit before Glenn’s voyage.

Many marriages ended in divorce because of the excessive workload, Roberts noted. Turning to his wife, Sandra, he said proudly, “This gal’s been with me for 57 years.”

“Not that many,” she told him. “We’re going to be 55.”

“Fifty-five. That’s right, that’s right,” Roberts muttered.

“Golly, gosh, when you get old, you forget about numbers,” Schepp piped up.

NASA’s celebration of Glenn’s three-orbit, five-hour flight aboard the Friendship 7 capsule began Friday at Cape Canaveral. The festivities move to Columbus, Ohio, on Monday, the actual anniversary. Glenn will be honored at a gala at Ohio State; its school of public affairs bears his name.

His wife of 68 years, Annie, who turned 92 Friday, and their two children are accompanying him to all the festivities.

Glenn served in the U.S. Senate for 24 years, representing his home state of Ohio. He ran for president in 1984. He returned to space in 1998 aboard shuttle Discovery, becoming the oldest spaceman ever at age 77.

Carpenter told the crowd Saturday that he’s still waiting for his first shuttle ride, drawing a big laugh.

The Mercury 7 astronauts were immortalized in Tom Wolfe’s 1979 book about the space program, “The Right Stuff,” which was later made into a movie. (Ed Harris portrayed Glenn in that movie.)

Although Wolfe suggested the nation will never see another hero of Glenn’s stature, Carpenter noted, “Maybe one day before too long the great hero John Glenn himself may be replaced by another national hero who represents the command of a Mars crew returned safely.”

“John, thank you for your heroic effort and all of you for your heroic effort,” Carpenter told the Mercury old-timers. “But we stand here waiting to be outdone.”